#banniere{

height:200px;
width:100%;

margin-top:0px;
margin-left:0px;

background-color:blue;

}

#menu{

height:30px;
width:100%;

margin-top:10px;
margin-left:0px;

background-color:orange;

}

#contenu{

width:100%;

margin-top:10px;
margin-left:0px;

background-color:grey;


}